I get my numbers from people on this board. Miles/kwh takes into account vehicle efficiency, I'm talking strictly charging efficiency. 25% loss is terrible.
How so? Have any LEAF packs been damaged from overheating?
So do I. There are numerous owners who get around 3 miles per kwh wall to wheel consistently with the roadster. The leaf is able to match that energy usage, but no one has reported getting any better(leaf forums).
It's hard to compare because of different drivers/roads, but it's not like the Leaf is more efficient to operate.
I didn't insinuate overheating of the Leaf pack. The very few instances of a Leaf in cold climate has the battery losing massive range due to cold temps and heater use. As of right now the Leaf is much less efficient than a roadster, in cold weather. I'm sure Nissan could work on this and improve, but I'm comparing existing vehicles.